1. Field of the Invention
The present invention relates to an apparatus with a video index function such as video cassette recorders (VCRs) and camcorders using a video tape, and more particularly to a video library system wherein index information is recorded on a control track of a tape and is detected during the vertical blanking period of a video signal while recording or reproducing the video signal with respect to video tape to thereby allow a portion desired by a user to be searched with a simple operation of function keys. A method for improved searching is also disclosed.
2. Description of the Prior Art
In order to find a video signal of a desired portion among recorded contents on a video tape, a video index search system (VISS) and a video address search system (VASS) are employed in apparatuses such as VCRs and camcorders using the video tape. A classification label may be attached on the video tape. The VISS is utilized to facilitate the search of recorded contents on the video tape during playing thereof by storing a specific index signal on a control track of the video tape in advance at the start point of recording. The VASS facilitates the search of recorded contents on the video tape during playing thereof by storing a specific index address on the control track of the video tape in advance at the start point of recording. The specific address corresponds to a point of the video tape at which the recording begins, and value of the specific address differs according to the recording point.
However, the adoption of the VISS or VASS has the following problems in searching the recorded contents on the video tape.
With VISS, since each index signal recorded on every recording point is the same throughout the video tape, the video tape must be played from its beginning to the end when searching for the desired contents. With VASS, a fixed address can be utilized when the exact position of the desired content from the start point of the search is already perceived. When the position of the desired content is not definite, the search must be performed from the start point of the search to the end of the video tape or must be performed after rewinding the video tape. If a desired picture is not then displayed, unsearched portions must be searched. Consequently, all contents recorded on the video tape should be searched.
To search the recorded contents on the video tape, the present invention employs a video library system (hereinafter referred to as "VLS") which does not adopt VISS or VASS and does not require labelling on the video tape. The VLS stores information data on the video tape to inform the user of information data about the video tape. In other words, when one video tape among several tapes is inserted into a set (e.g., VCR), information indicating the order of the inserted tape among the tapes and information registered by the user during recording are inserted to inform the user of the location of the recorded content. Then, the information about the video tape is recorded or played, using a remote controller or key board installed on the set.
A technique for recording and playing message data in a vertical blanking period is disclosed by U.S. Pat. No. 5,097,348. However, this technique utilizes only a superimposition function.